Credit card validity is primarily checked today by viewing loose booklets or papers separately supplied by each different credit organization. These booklets or papers are easily misplaced and are time-consuming to utilize. While numerous automated credit card validity checking devices have heretofore been proposed, these have generally involved expensive digital computer type systems which scan machine readable lists and provide a signal indicating validity status.
In my opinion, such cumbersome equipment could be avoided by merely mechanizing a way for an updated list image of invalid credit card numbers, in proper alpha-numeric sequence to be serially run past a viewing area to allow the human eye to make the necessary comparison with a credit card to be checked.